1. Field of the Invention
The present invention relates to apparatus for the detection of surface defects especially on cylindrical objects such as nuclear fuel pellets.
2. Discussion of Prior Art
Certain cylindrical objects such as nuclear fuel pellets have to meet very demanding manufacturing quality specifications. Such objects may be manufactured by an automated manufacturing route without handling by human operators and in such a route it will be necessary to inspect the objects for surface defects using automatic apparatus. The objects may for example be sintered cylindrical UO.sub.2 (uranium dioxide) pellets for a so-called "agr" fuel element. Such pellets have an axial hole or bore provided for fuel performance reasons. The sintered pellets are inserted in stainless steel cladding tubes, the tubes being sealed to form a fuel pin and a cluster of pins being assembled to form fuel elements. The pellets require automatic inspection before insertion in the cladding tubes.